Device and method for mixing and dispensing a bone cement mixture

ABSTRACT

In at least one embodiment of the present invention, a device for mixing and dispensing a bone cement mixture is provided. The device comprises a first chamber and a second chamber. The first chamber is for containing a first bone cement component. The second chamber is for containing a second bone cement component. A valve is in fluid communication with the first and second chambers. A first and a second plunger are respectively within the first and second chambers and are configured to actuate within their respective chambers. When the valve is in a first position actuating the first plunger advances the first bone cement component into the second chamber to form the bone cement mixture.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a device, a kit and a method for mixingand dispensing a bone cement mixture.

2. Background

There is a clinical need to fill and stabilize damaged bones ofpatients, such as for example, filling defects in collapsed vertebra ofpatients suffering from severe back pain caused by osteoporosis,metastatic tumors or back injuries. Currently, these defects arerepaired using multi-component bone cements that are mixed in opencontainers, transferred to a device and injected into the damaged bonewhere the mixture chemically reacts or cures to form a solid supportstructure.

The most widely used bone cements are based on polymethylmethacrylate(PMMA) and hydroxyapatite. These materials have relatively good strengthcharacteristics, but have a number of drawbacks. These cements are atwo-part chemically reactive system and have approximately five to tenminutes of working time once the components are mixed. As for examplewith the PMMA based system, one of the components is a liquid monomermethylmethacrylate (MMA), which is noxious and toxic to handle. Theother component, the polymer component PMMA, is a powder that can bedifficult to mix thoroughly. Moreover, current methods of mixing thesetwo components together are typically done by hand in an open containeror dish. This procedure permits significant vaporization of the noxiousliquid monomer MMA. Also, the working time increases between mixing anddispensing because once the mixture is mixed it then needs to betransferred to a syringe for injection into the damaged bone. Moreover,the working time is limited because the viscosity of the cementconstantly increases during mixing, thus making transferring of themixture to the syringe and injection of the mixture into the damagedbone more difficult. Often, very high injection pressures and/or largebore needles may be necessary to inject the mixture, especially if it'snear the end of the cements working time.

BRIEF SUMMARY OF THE INVENTION

Embodiments of the present invention provide a device, a kit and amethod that facilitates mixing and dispensing of the bone cement mixturesuch that the interventionalist and the patient have minimal exposure tothe noxious vapors of the monomer as well as providing more flexibleworking times for suitable injection-ability of the mixture into thedamaged bone.

In at least one embodiment of the present invention, a device for mixingand dispensing a bone cement mixture is provided. The device comprises afirst chamber and a second chamber. Each chamber has a proximal end anda distal end. The first chamber is configured for containing a firstbone cement component and the second chamber is configured forcontaining a second bone cement component. A first plunger and a secondplunger are disposed cooperatively within the first and second chambers,respectively, and configured to actuate within the correspondingchamber. In fluid communication with the first and second chambers is avalve proximate the distal ends of the first and second chambers. Thevalve includes a first position configured to cooperate with the firstplunger during actuation of the first plunger to advance the first bonecement component from the first chamber into the second chamber. Withinthe second chamber, the first bone cement component mixes with thesecond bone cement component to form the bone cement mixture. An outletis in fluid communication with the valve for dispensing the bone cementmixture from the device.

In at least one other embodiment of the present invention, a bone cementsubstitute kit for mixing a bone cement mixture and dispensing the bonecement mixture into a damaged bone of a patient is provided. The kitcomprises a first bone cement component and a second bone cementcomponent. A device includes a first chamber and a second chamber. Eachchamber has a proximal end and a distal end. The first chamber isconfigured for containing the first bone cement component and the secondchamber is configured for containing the second bone cement component. Afirst plunger and a second plunger are disposed cooperatively within thefirst and second chambers, respectively, and configured to actuatewithin the corresponding chamber. In fluid communication with the firstand second chambers is a valve proximate the distal ends of the firstand second chambers. The valve includes a first position configured tocooperate with the first plunger during actuation of the first plungerto advance the first bone cement component from the first chamber intothe second chamber. Within the second chamber, the first bone cementcomponent mixes with the second bone cement component to form the bonecement mixture. An outlet is in fluid communication with the valve fordispensing the bone cement mixture from the device. In fluidcommunication with the outlet is a needle configured for receiving thebone cement mixture from the device and for advancing the bone cementmixture into the damaged bone of the patient.

In at least one other embodiment of the present invention, a method formixing a bone cement mixture and for dispensing the bone cement mixtureinto a damaged bone of a patient is provided. The method comprisesproviding a device including a first chamber and a second chamber. Boththe first and second chambers have a proximal end and a distal end. Avalve located proximate the distal ends of the first and second chambersis in fluid communication with the first and second chambers. A firstplunger and a second plunger are disposed cooperatively within the firstand second chambers, respectively, and are configured to actuate withintheir corresponding chamber. The first bone cement component isintroduced into the first chamber. The second bone cement component isintroduced into the second chamber. The first bone cement component ismixed with the second bone cement component which includes positioningthe valve in a first position and actuating the first plunger to advancethe first bone cement component into the second chamber such that thefirst bone cement component mixes with the second bone cement componentto form the bone cement mixture within the second chamber. A needle influid communication with the device is inserted into the damaged bone ofthe patient. Via the needle, the bone cement mixture is dispensed fromthe device into the damaged bone of the patient. The bone cement iscured to stabilize the damaged bone of the patient.

Further objects, features and advantages of the invention will becomeapparent from consideration of the following description and theappended claims when taken in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a collapsed vertebra;

FIG. 2 is a partial side view of a device for stabilizing a collapsedvertebra in accordance with one embodiment of the present invention;

FIG. 3 is an enlarged view of FIG. 2;

FIG. 4 is a perspective view of a device for stabilizing a collapsedvertebra in accordance with another embodiment of the present invention;

FIG. 5 is a partial side view of a device for stabilizing a collapsedvertebra in accordance with yet another embodiment of the presentinvention;

FIG. 6 is a partial side view of a stabilized collapsed vertebra inaccordance with one example of the present invention;

FIG. 7 is a partial side view of a device for stabilizing a collapsedvertebra in accordance with another embodiment of the present invention;

FIG. 8 a is a side view of a bone cement substitute kit in accordancewith one embodiment of the present invention; and

FIG. 8 b is an exploded view of the bone cement substitute kit depictedin FIG. 8 a.

DETAILED DESCRIPTION OF THE INVENTION

Details embodiments of the present invention are disclosed herein. It isunderstood however, that the disclosed embodiments are merely exemplaryof the invention and may be embodied in various and alternative forms.The figures are not necessarily to scale; some figures may be configuredto show the details of a particular component. Therefore, specificstructural and functional details disclosed herein are not to beinterpreted as limiting but merely as a representative basis with theclaims and for teaching one skilled in the art to practice of thepresent invention.

Examples of the present invention seek to overcome some of the concernsassociated with stabilizing and/or repairing the damaged bone of apatient with a bone cement while minimizing toxic effects to both thepatient and the interventionalist, and enhancing the ease of handling ofthe bone cement for both mixing and introduction into the damaged bone.

Employing the principles of the present invention is, for example, adevice, a kit and a method for stabilizing and/or repairing a damagedbone of a patient. The device, which is utilized in both the kit and themethod, is a closed mixing and dispensing system having two chambersthat are in fluid communication with one another. Each chamber isinitially for containing, for example, one of the components of a twocomponent bone cement system. The device is configured such that thefirst bone cement component can be advanced from the first chamber intothe second chamber so as to mix with the second bone cement component inthe second chamber to form a bone cement mixture. The bone cementmixture, if needed, can be subsequently advanced back into the firstchamber and vice versa until the bone cement mixture is thoroughlymixed. The device may also be in fluid communication with a needleinserted into the damaged bone of a patient. The device is configuredsuch that the bone cement mixture may be advanced from the device intothe damaged bone of a patient via the needle. The device preferablymixes the bone cement components together without releasing noxiousmonomer fumes contained in one of the bone cement components. Moreover,since the device is configured to dispense the bone cement mixture thereis no need for transferring the mixture from another source into thedevice. Accordingly, the device minimizes the mixing and dispensing timeof the bone cement and thus, enhances the remaining working time forintroducing the mixture into the damaged bone. Once the bone cement isintroduced into the damaged bone of the patient it cures to form a solidstructure which stabilizes the bone.

Referring now to the drawings, FIG. 1 illustrates a vertebra 10 whichincludes a collapsed vertebra 12 with a compression fracture 13. Thevertebra 10 may be for example in the thoracic or lower spine of thepatient. In the compression fracture 13 of the vertebra 12, the bonetissue of the vertebral body collapses. This condition is commonlycaused by osteoporosis and less often by a tumor, or trauma to the back.

Referring now to FIGS. 2 and 3, at least one embodiment of the presentinvention is provided. The collapsed vertebra 12 may be stabilized byeither verteborplasty or kyphoplasty, both of which are medicalprocedures for introducing bone cement into the collapsed vertebra.These procedures stabilize the collapsed vertebra by filling in openspaces within the vertebra 12 to provide a more continuous and solidform. Kyphoplasty may further stabilize the vertebra 12 by restoringvertebral spacing which alleviates nerve pinching from the vertebra 12.It should be noted that the present invention applies to both of thesemedical procedures and other procedures for stabilizing and/or repairingdamaged bones of patients despite many of the various embodimentsdiscussed herein are described using verteborplasty.

Verteborplasty involves that a patient remain lying throughout theentire procedure. It is performed under a local anesthesia and/or alight sedative. A small nick is then made in the skin near the spine anda needle 14 is inserted percutaneously. As illustrated in FIG. 3, theneedle 14 may be inserted into the interior 15 of the vertebra 12, forexample via or through the left or right pedicle 17 of the vertebra 12.

Referring to FIGS. 5 and 6, the bone cement mixture 18 may be dispensedfrom a device (not shown) through the needle 14 and into the vertebra 12to form a solid structure 64 that supports the collapsed vertebra 12.The bone cement mixture 18 forms the solid structure 64 by chemicallyreacting or curing to become a solid. The stabilizing structure 64 maybe formed within and/or about the collapsed vertebra 12 and may helprestore vertebral spacing and alleviate nerve pinching by supporting thecollapsed vertebra 12 generally in at least a compressive mode.Preferably, the structure substantially fills in the open spaces 15 ofthe collapsed vertebra 12 providing a more dense and continuous vertebra12 which enhances mobility of the patient.

Referring to FIG. 4, at least one embodiment of a device for mixing abone cement mixture and for dispensing the mixture is provided. Thedevice 20 or novel syringe comprises a body 22 that includes a firstchamber 24 and a second chamber 30. The first chamber 24 has a proximalend 26 and a distal end 28. The second chamber 30 also has a proximalend 32 and a distal end 34. The two chambers 24 and 30 are preferablyjuxtaposed such that their distal ends 28 and 34 and the proximal ends26 and 32 are correspondingly positioned adjacent one another.

The first chamber 24 is initially for containing a first bone cementcomponent and the second chamber 30 is initially for containing a secondbone cement component. For example, a bone cement system may becomprised of separate components A and B. These components may be aliquid and/or a solid, which when mixed together chemically react toform a solid structure. Component A may be initially contained in thefirst chamber 24 and component B may be initially contained in thesecond chamber 30 or vice versa.

To further illustrate, component A, for example, is liquid monomer MMAwith a relatively low viscosity of about 0.6 centipoise at roomtemperature and component B is solid polymer powder of PMMA. When theMMA is mixed with the PMMA, a chemically reacting paste may be formedwhich continually increases in viscosity over a working time of about 5to 10 minutes to form a solid structure. In another example, component Amay be sodium phosphate and component B may be solid powder ofmonocalcium phosphate, tricalcium phosphate, calcium carbonate ormixtures thereof that form a chemically reacting solution when mixedwith sodium phosphate, which also increases in viscosity over a workingtime of about 5 to 10 minutes to form a solid structure.

A valve 36 may be located proximate the distal ends 28 and 34 of thefirst and second chambers. The valve 36 is in fluid communication withthe first and second chambers 24 and 30. In one example, the body 22further includes conduits 37 and 38 coupling the first and secondchambers 24 and 30, respectively with the valve 36. The valve 36 isconfigured for dispensing the bone cement mixture from the device 20 viaoutlet 39. In fluid communication with conduits 37 and 38, outlet 39allows the bone cement mixture to be dispensed therethrough towards thepatient. In one example, the valve 36 may be a three way valveselectively providing fluid communication between both chambers 24 and30 as well as providing exit of the cement mixture through the outlet 39for dispensing from either of the chambers 24 and 30. Moreover, thevalve 36 may also provide an inlet for receiving either or both of thebone cement components into their respective chambers 24 and 30.

The device 20 further comprises a first plunger 40 disposed within thefirst chamber 24 and configured to actuate within the chamber 24. Thedevice 20 further comprises a second plunger 42 that is disposed withinthe second chamber 30 and configured to actuate within the secondchamber 30. For example, the plungers 40 and 42 may actuate by slidingtowards the distal ends 28 and 34 of their respective chambers 24 and30. Moreover, in one example, either or both plungers may be free toslide towards the proximal ends 26 and 32 in response to an increase inpressure within their respective chamber 24 and 30. This may be due, forexample, from monomer vapor pressure build-up within the respectivechamber or a bone cement component or mixture being advanced from theother chamber into the respective chamber.

In at least one embodiment, one of the first and second plungers 40 and42 is a screw-gear plunger 44, shown in this example as the secondplunger 42. The screw-gear plunger 44 includes grooves 46 formed on ashaft 47 of the plunger 44 and a handle 48 disposed at the proximal endof the shaft 47.

The screw-gear plunger 44 has a corresponding chamber, shown in thisexample as the second chamber 30, which is a high pressure injectionchamber 50. The high pressure chamber 50 is adapted for withstandingpositive displacement pressures associated with advancing “paste like”fluids through the conduit 38 and valve 36. In one example, theviscosity of the “paste like” fluid is greater than about 1,000centipoise. The high pressure chamber may be made of glass or othersuitable materials known in the art for high pressure devices.

In this embodiment, the high pressure injection chamber 50 includes alocking device 52 which includes a cam 54. The locking device 52 may bedisposed about the plunger shaft 47 and disposed at the proximal end 32of the chamber 50. When the locking device 52 is in a locked position,the cam 54 engages the grooves 46 and the screw-gear plunger 44 isactuated by turning the handle 48 where the cam 54 and the grooves 46cooperate to advance the screw gear plunger 44 towards the distal end 34of the high pressure chamber 50. When the locking device 52 is in anunlocked position, the cam 54 is disengaged or spaced apart from thegrooves 46 and the screw-gear plunger 44 is actuated by pushing thehandle 48 of the screw-gear plunger 44 towards the distal end 34 of thehigh pressure injection chamber 50.

The valve 36 preferably has at least a first position and a secondposition. In one example, when the valve 36 is in the first position,actuating the first plunger 40 advances the first bone cement componentfrom the first chamber 24 into the second chamber 30 such that the firstbone cement component mixes with the second bone cement component toform the bone cement mixture within the second chamber 30. With thevalve 36 still in the first position, the second plunger 42 may then beactuated to advance the bone cement mixture from the second chamber 30into the first chamber 24. This process of advancing the bone cementmixture between the chambers 24 and 30 may be repeated until the bonecement components are thoroughly mixed together to the satisfaction ofthe interventionalist.

When the valve 36 is in a second position, actuating one of the firstand second plungers 40 and 42 dispenses the bone cement mixture from thedevice 20 by advancing the mixture from the corresponding chamber 24 and30 through the valve 36 and the outlet 39. In at least one embodiment,the plunger that is used to dispense the cement mixture from the device20 is the screw-gear plunger 44. In this example, the locking device 52is in a locked position such that the cam 54 engages the grooves 46 onthe shaft 47. The handle 48 is turned by the interventionalist and thescrew-gear plunger 44 advances the bone cement mixture from the highpressure injection chamber 50 through the valve 36 thereby dispensingthe mixture from the device 20. Alternatively, the other plunger 40 maybe actuated by pushing the plunger towards the distal end 28 of thefirst chamber 24 to dispense the bone cement mixture from the firstchamber 24. This procedure may be used when the bone cement mixture hasa relatively low viscosity. Whereas, the screw-gear plunger 44 maypreferably be used to dispense the bone cement mixture when theviscosity of the mixture is relatively high.

The device 20 may further include as part of the valve 36, a Lurefitting nozzle 56. The bone cement mixture may be dispensed from theoutlet 39 of the device 20 through the Lure fitting nozzle 56. The Lurefitting nozzle 56 typically has a tapered end 58 that facilitatesconnecting to various types of cannula, tubing, needles or other similarmedical devices.

In at least one embodiment, the device 20 further comprises an end cap60 disposed at the proximal ends 26 and 32 of the first and secondchambers 24 and 30 that forms a closure for both chambers 24 and 30. Theend cap 60 may also include the locking device 52. The end cap 60provides an interface for positioning each of the plungers 40 and 42,preferably concentrically, within the corresponding chambers 24 and 30.Moreover the end cap 60 may also include two hook shaped handles 61 and62 which are disposed at opposite ends of the end cap 60 which are forgripping the device 20 by an interventionalist.

In at least one embodiment, the handle 48 of the screw-gear plunger 44is positioned along the shaft 47 and disposed outside of the highpressure chamber 50 and has, for example, a triangular shape forfacilitating turning of the screw-gear plunger 44. Alternatively, theother plunger 40 may have a handle 49 positioned along a shaft 51 whichis disposed outside the corresponding chamber 24 that has, for example,a flat disk shape to facilitate pushing of the plunger 40 towards thedistal end 28.

Referring to FIG. 7, at least one other embodiment for stabilizing acollapsed vertebra 12 of a patient is provided. The method includesplacing a balloon 66 into the collapsed vertebra 12. The balloon 66 maybe positioned in the vertebra 12 for example via the needle 14, acatheter or mandrel. The balloon 22 is then filled with the bone cementmixture and sealed. The balloon 66 may be sealed for example by twistingthe needle 14 and shearing the corresponding end portion of the balloon66 or alternatively by applying any suitable adhesive, such as acyanoacrylate, to the end portion. The cement mixture within the sealedballoon 66 cures to form a solid support structure 64 within thecollapsed vertebra 12.

The balloon 66 may be made of any suitable material used for medicalintracorporeal balloon devices. However, a polymer impermeable to bodyfluids and MMA may be preferred. An example of such material ispolyethylene terephthalate (PET) or polybutylene terephthalate (PBT).

The interventionalist may also assess whether the collapsed vertebra 12is sufficiently filled via fluoroscopy. If the collapsed vertebra 12 isnot sufficiently filled, an additional balloon may be placed within thecollapsed vertebra 12 and the filling, solidifying and/or curing andsealing steps may be repeated.

Referring also to FIGS. 8 a and 8 b, at least one embodiment of a bonecement substitute kit is provided. The kit includes a device 20 asdiscussed in the forgoing paragraphs as well as the needle 14 which isconfigured for fluid communication with the device 20 and for advancingthe bone cement mixture into the collapsed vertebra 12. The needle 14may have a beveled edge end 68 for easy insertion and removal from thecollapsed vertebra 12. The other end 70 of the needle 14 may be directlycoupled to the device 20 or indirectly coupled via tubing 72. The tubing72 provides fluid communication between the device 20 and the needle 14.Preferably, the tubing 72 may be flexible to facilitate maneuvering ofthe device 20 during injection of the bone cement into the damaged bone.

The kit may further comprise a sealed envelope 74 containing a componentof the bone cement, such as PMMA, and sealed container 76 containing theother component of the bone cement, such as MMA. Alternatively, eitheror both the first and second components of the bone cement may alreadybe contained within the first and second chambers 24 and 30 of thedevice 20 as packaged.

In at least one embodiment, the device 20 includes a third position forthe valve 36, which closes off fluid communication between both chambers24 and 30 and between the chambers 24 and 30 and the outlet 39. Thethird position of the valve 39 may facilitate packaging and handling ofthe kit when the bone cement components are pre-packaged within theirrespective chambers 24 and 30. Additionally, the kit may further includea balloon 66 (shown in FIG. 7) for receiving the bone cement mixture 18.

As a person skilled in the art will readily appreciate, the abovedescription is meant as an illustration of the implementation of theprinciples of this invention. This description is not intended to limitthe scope or application of this invention in that the invention issusceptible to modification variation and change, without departing fromthe spirit of this invention, as defined in the following claims.

1. A device for mixing and dispensing a bone cement mixture, the devicecomprising: a first chamber and a second chamber each having a proximalend and a distal end, the first and second chambers being configured tocontain respectively a first bone cement component and a second bonecement component; a first plunger and a second plunger disposedcooperatively within the first and second chambers, respectively, andconfigured to actuate within the corresponding chamber; a valveproximate the distal ends of the first and second chambers and being influid communication with the first and second chambers, the valveincluding a first position being configured to cooperate with the firstplunger during actuation of the first plunger to advance the first bonecement component from the first chamber into the second chamber suchthat the first bone cement component mixes with the second bone cementcomponent to form the bone cement mixture within the second chamber; andan outlet in fluid communication with the valve for dispensing the bonecement mixture from the device, wherein one of the first and secondplungers is a screw-gear plunger including grooves and a handle andwherein the corresponding chamber is a high pressure injection chamberincluding a locking device having locked and unlocked positions, thelocking device including a cam configured to engage the grooves in thelocked position, the screw-gear plunger being actuated by turning thehandle, cooperating the cam and the grooves to advance the screw-gearplunger towards the distal end of the high pressure chamber, the camconfigured to disengage from the grooves in the unlocked position, thescrew-gear plunger being actuated by pushing the screw-gear plungertowards the distal end of the high pressure injection chamber.
 2. Thedevice according to claim 1 wherein the valve in the first position isconfigured to cooperate with the second plunger during actuation of thesecond plunger to advance the bone cement mixture from the secondchamber into the first chamber.
 3. The device according to claim 1wherein the valve includes a second position being configured tocooperate with one of the first and second plungers during actuation ofthe one of the first and second plungers to dispense the bone cementmixture from the device.
 4. The device according to claim 1 wherein theone of the first and second plungers is configured to be actuated bypushing the plunger towards the distal end of the corresponding chamber.5. The device according to claim 1 wherein the screw-gear plunger isconfigured to dispense the bone cement mixture from the high pressureinjection chamber by turning the handle when the locking device is inthe locked position.
 6. The device according to claim 1 wherein thefirst and second chambers are juxtaposed and include an end capproximate the proximal ends of the first and second chambers, the endcap including the locking device and providing an interface forpositioning each of the plungers within the corresponding chamber.
 7. Abone cement substitute kit for mixing a bone cement mixture anddispensing the bone cement mixture into a damaged bone of a patient, thekit comprising: a first bone cement component and a second bone cementcomponent; a device including: a first chamber and a second chamber eachhaving a proximal end and a distal end, the first and second chambersbeing configured to contain respectively the first and second bonecement components; a first plunger and a second plunger disposedcooperatively within the first and second chambers, respectively, andconfigured to actuate within the corresponding chamber; a valveproximate the distal ends of the first and second chambers and being influid communication with the first and second chambers, the valveincluding a first position being configured to cooperate with the firstplunger during actuation of the first plunger to advance the first bonecement component from the first chamber into the second chamber suchthat the first bone cement component mixes with the second bone cementcomponent to form the bone cement mixture within the second chamber; andan outlet in fluid communication with the valve for dispensing the bonecement mixture from the device; and a needle in fluid communication withthe outlet and configured for receiving the bone cement mixture from thedevice and for advancing the bone cement mixture into the damaged boneof the patient.
 8. The kit according to claim 7 wherein the valve in thefirst position is configured to cooperate with the second plunger duringactuation of the second plunger to advance the bone cement mixture fromthe second chamber into the first chamber.
 9. The kit according to claim7 wherein the valve includes a second position being configured tocooperate with one of the first and second plungers during actuation ofthe one of the first and second plungers to dispense the bone cementmixture from the device.
 10. The kit according to claim 9 wherein thevalve includes a third position that closes off fluid communicationbetween the first and second chambers and the outlet, and wherein thekit is packaged such that the valve is in the third position and thefirst and second bone cement components are contained respectivelywithin the first and second chambers.
 11. The kit according to claim 7further comprising a tubing configured to couple to both the device andthe needle and to provide fluid communication between the device and theneedle.
 12. The kit according to claim 7 wherein one of the first andsecond plungers is a screw-gear plunger including grooves and a handleand wherein the corresponding chamber is a high pressure injectionchamber including a locking device having locked and unlocked positions,the locking device including a cam configured to engage the grooves inthe locked position, the screw-gear plunger being actuated by turningthe handle, cooperating the cam and the grooves to advance thescrew-gear plunger towards the distal end of the high pressure chamber,the cam configured to disengage from the grooves in the unlockedposition, the screw-gear plunger being actuated by pushing thescrew-gear plunger towards the distal end of the high pressure injectionchamber and wherein the one of the first and second plungers isconfigured to be actuated by pushing the plunger towards the distal endof the corresponding chamber.
 13. The kit according to claim 12 whereinthe screw-gear plunger is configured to dispense the bone cement mixturefrom the high pressure injection chamber by turning the handle when thelocking device is in the locked position.
 14. The kit according to claim7 further comprising a balloon configured for positioning within thedamaged bone of the patient and for receiving the bone cement mixturefrom the needle.
 15. A method for mixing a bone cement mixture anddispensing the bone cement mixture into a damaged bone of a patient, themethod comprising: providing a device including a first chamber and asecond chamber each having a proximal end and a distal end, a valveproximate the distal ends of the first and second chambers and in fluidcommunication with the first and second chambers, and a first plungerand a second plunger disposed cooperatively within the first and secondchambers, respectively, and configured to actuate within thecorresponding chambers; introducing the first bone cement component andthe second bone cement component respectively into the first and secondchambers; mixing the first bone cement component with the second bonecement component including: positioning the valve in a first position;and actuating the first plunger to advance the first bone cementcomponent into the second chamber such that the first bone cementcomponent mixes with the second bone cement component to form the bonecement mixture within the second chamber; inserting a needle into thedamaged bone of the patient, the needle being in fluid communicationwith the device; dispensing the bone cement mixture from the device intothe damaged bone of the patient via the needle; and curing the bonecement mixture to stabilize the damaged bone of the patient.
 16. Themethod according to claim 15 further comprising positioning a balloonwithin the damaged bone of the patient and the step of dispensing thebone cement mixture includes receiving the bone cement mixture into theballoon via the needle.
 17. The method according to claim 15 wherein thestep of mixing the first bone cement component with the second bonecement component further includes actuating the second plunger toadvance the bone cement mixture from the second chamber into the firstchamber.
 18. The method according to claim 15 wherein the step ofdispensing the bone cement mixture from the device includes positioningthe valve in a second position and actuating one of the first and secondplungers to advance the bone cement mixture from the correspondingchamber into the needle.
 19. The method according to claim 15 whereinone of the first and second plungers is a screw-gear plunger includinggrooves and a handle and the corresponding chamber is a high pressureinjection chamber including a locking device having locked and unlockedpositions, the locking device including a cam, configured to engage thegrooves in the locked position, wherein the step of dispensing the bonecement includes positioning the locking device into a locked position,turning a handle of the screw-gear plunger where the cam and the groovescooperate to advance the screw-gear plunger towards the distal end ofthe high pressure chamber causing the bone cement to advance from thehigh pressure chamber into the needle.